[5.9] Disable TempRValueOpt when there are users of the temp object preceding the copy #66342
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meg-gupta
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@swift-ci test |
nate-chandler
approved these changes
Jun 5, 2023
tbkka
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Jun 5, 2023
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Explanation: TempRValueOpt did not check if the temp obj has any users before its initializing copy before optimizing it away. This can happen with projection users. Doing so, led to invalid SIL because of use before def after the optimization.
Scope: Narrow; Disabled TempRValueOpt on an edgecase, without it, the compiler would have crashed anyway in IRGen.
Risk: Low; Disabling an edge case, do not expect to have any associated risk.
Reviewed by: @atrick @nate-chandler
Issue: rdar://108361427
Original pull request: #66328